398 



DISEASES OF THE SKIN. 



rule, upon the hair and epidermis, and are particularly found on 

 the head and neck. Both skin parasites produce intense irritation 



Fig. S7. 



Fig. 



Haematopinus piliferus 



Trichodectes latus. 



Tlie accompanying small lines give the uatural size of tlie parasite. 



and rubbing, causing infiammatory efflorescences . which look very 

 much like squamous eczema, with partial loss of hair and forma- 

 tion of scabs. The diagnosis is usually easy, as we can see the 

 parasites and their eggs by separating the hair. 



Theeapeutic Treatment. This consists of destroying the 

 parasites and their eggs. For that purpose it is often requisite 

 to clip the animals. The safest and least harmful agents are 

 decoctions of tobacco (5 to 10 per cent.), solutions of creolin 

 (3 to 6 per cent.), petroleum (pure, or mixed with olive oil), and 

 in small dogs anise-seed oil (1 to 10 per cent, of olive oil). Mer- 

 curial ointment may be rubbed in the neck around the collar, but 

 we must not apply more than a piece the 

 size of a bean. Washing with corrosive sub- 

 limate solution has been tried, but it must 

 be very carefully done, and the animal not 

 allowed to lick the body, as it is very apt to 

 produce mercurial symptoms and salivation. 



Fig. 



Ixodes Ricinus. 



This parasite, which is about 2 mm. in 



Ixodes ricinus. The ae- ^^S*' ^"'^ sOmetimes when full grown al- 

 companying line is the na- most 3 mm., looks very much like an acari 



tural size of the parasite, ^-jj,. ^^.v -j., 



(KucHBNMEisTEE-zuRN.) (.-fig- ov ) . it pBuetrates into the skin 



